Re: newbie myHead question
- To: mathgroup at smc.vnet.net
- Subject: [mg47044] Re: newbie myHead question
- From: drbob at bigfoot.com (Bobby R. Treat)
- Date: Mon, 22 Mar 2004 05:18:59 -0500 (EST)
- References: <c3h1jj$bc8$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Here are a couple of methods.
m={{a,b},{a,b},{a,b}};
n=myHead@@m;
myHead@@Transpose@(List@@n)
Head[n]@@Transpose@(List@@n)
myHead[{a,a,a},{b,b,b}]
myHead[{a,a,a},{b,b,b}]
Bobby
János <janos.lobb at yale.edu> wrote in message news:<c3h1jj$bc8$1 at smc.vnet.net>...
> I have
>
> m = {{a, b}, {a, b}, {a, b}}
>
> When I apply Transpose to it, I will have
>
> Transpose[m]
>
> {{a, a, a}, {b, b, b}}
>
> The FullForm of it is
>
> List[List[a, a, a], List[b, b, b]]
>
> Now, if I do
>
> n = Apply[myHead, m]
>
> I get
>
> myHead[{a, b}, {a, b}, {a, b}]
>
> If I apply Transpose to it, I get
>
> Transpose[n]
>
> Transpose[myHead[{a, b}, {a, b}, {a, b}]]
>
> The FullForm of it
>
> Transpose[myHead[List[a, b], List[a, b], List[a, b]]]
>
> which is not that I need. I need
>
> myHead[{a,a,a},{b,b,b}]
>
> or
>
> myHead[List[a, a, a], List[b, b, b]]
>
> What am I missing ? What should I do to get myHead[{a,a,a},{b,b,b}] ?
>
> Thanks ahead,
>
> János
> -------------------------------------------------
> clear perl code is better than unclear awk code; but NOTHING comes
> close to unclear perl code
> http://www.faqs.org/faqs/computer-lang/awk/faq/